History of the World: Cockroaches were there

Cockroaches have been around for more of the history of the world than almost any other creature. Fossils of cockroaches from the Carboniferous period date to 250 million years ago. The fossil record shows that cockroaches were extremely abundant at a time in the earth's history when humidity was high and vegetation lush.

More than 3,500 species of cockroaches have been identified and they are very similar in appearance to their fossil ancestors. It appears that cockroaches are one of nature's success stories.

Most species of cockroaches are associated with the tropical regions of the earth where they live outdoors and feed on dead plant and animal material. Other than in the tropics or subtropics, cockroaches live in structures provided by humans — the buildings we use as homes and businesses. Cockroaches sometimes do live outdoors in northern climates during the summer months, but to survive they must come indoors when the weather turns cold.

Only 57 of the 3,500 species of cockroaches are found in the United States. Texas has the honor of being the state having the greatest number of cockroach species residing within its boundaries. Thirty-two cockroach species can be found in Texas, probably because of the great range of ecological habitats within its borders.

Fortunately, only a few cockroach species have taken to living in our homes and businesses. Three of these pest species are called the German cockroach, the Oriental cockroach and the American cockroach. Their names seem to suggest their national origin. However, such names can be deceiving.

The German cockroach is the most common species found in homes of the United States. This insect appears to have originated in Northeast Africa, finding its way to Europe on Greek and Phoenician ships many centuries ago. Once in western Europe, it was distributed by commerce to all parts of the world.

The so-called Oriental cockroach is also a native of North Africa, but probably got its name from specimens taken in the United States, where the insect had been introduced from the Orient. This insect, like the German roach, also spread by hitching rides on early trading vessels in the Mediterranean Sea.

The American cockroach, the largest of the cockroach species, most likely also originated in Africa. It has been suggested that slave ships from the West African coast provided the means of introduction into South America, the West Indies and the southern part of the United States.

The names of some of our most common cockroach pests probably don't tell us much about where these insects originated. However, the names do indicate that cockroaches are some of the most accomplished travelers of the insect world, hitching a ride anywhere they can.

Even today these world travelers aren't above jumping in a box or bag for a short ride from one building to another!